Go on YouTube and you’ll find white YouTubers discovering they have Asian heritage for the first time. Yes, in an age of advanced technology, anyone can now discover their ancestral ethnicity with just one easy DNA test. Many commercial DNA registries offer to examine your DNA and determine your ancestors’ ethnicity, and usually, the results are not what you would expect. And it doesn’t even cost much – some can do it as a birthday gift or just for fun.

But how does it work?

How DNA Tests Trace Your DNA

Commercial companies such as 23andMe and Ancestry break down your DNA. Half of your DNA comes from one parent, and the other half comes from another. That half from your parent is a combination of blocks called haplotypes. These haplotypes are millions of building blocks forming a sequence. When you look at your DNA and match it with your parents’ DNA, you can see which sequences come from them. And when you have offspring of your own, your DNA gets broken down into smaller bits and combined into that of your spouse to form your offspring’s DNA.

If you take the DNA of various groups around the world, you’ll find that a lot of them in one area have similar sequences. So, if you were to have their DNA tested, these companies would look at your DNA sequence and try to find similar haplotypes in different ethnicities. And because older generations have less broken-down haplotypes, you can determine how far away your ancestor is from you. Smaller chunks mean that your ancestor of a different ethnicity could date back centuries.

How Does It Work?

There are multiple companies that offer DNA testing services – 23andMe, Ancestry.com, National Geographic – and while some used to market their services as health testers to test for genetic diseases, this is no longer the case thanks to advertising regulations since their services cannot guarantee accurate detection. Instead, they now promote their “ancestry” services to help them connect with lost relatives and find where their ancestors came from.

You can buy at-home DNA testing kits from these companies. These kits instruct you how to collect spit samples, which you then send to the company for analysis. Around two months later, you log on to the company’s website and find the results about their paternal and maternal ancestry.

During the two-month period, the company digitizes your DNA sequence into G, T, C, and A’s, which are the four nucleobases of the DNA. From there, computers follow an algorithm to pull meanings out of the letter sequences. The computers are looking for patterns found in various ethnicities based on references of DNA groups installed by the company.

How Accurate Is It?

Unfortunately, DNA tests can’t tell you that your ancestors were wheat farmers in a small rural town in Russia. Nor can they tell you that your ancestors moved to the United States during the war and five generations have already been living there (though it’s logical to infer that they came from their original country at one point). They can tell you’re your ethnicity, but not where they come from.

Tests analyze your DNA and compare it to other populations around the world. The results are just an estimate, and it’s not going to be very specific. Considering that DNA and biology do not recognize the political borders and cultural divisions in neighboring countries, if you have Russian ancestry, you would never know because a Russian’s DNA looks similar to those in Romania and Poland, so your results would only say “Eastern European.” However, you can tell your ancestor’s nationality if the DNA belongs to an isolated population, such as those in Iceland.

It’s also accurate enough for you to find distant cousins who share a common ancestor with you. If you take a DNA test and their DNA is on a database, you can find that you are related to a common ancestor. However, a database is only as accurate as the amount of data they have to work with. For example, Europeans are the largest sampled groups in 23andMe, so it’s likely their results can say you’re British, Eastern European, Anglo-Saxon and other types of European ethnicities. However, because the least sampled group is the Native American population, you won’t find results separating the Inuits from the Navajos, and instead you’ll find the general Native American category, since there’s not enough data to be even more specific.

The Benefits

More people are taking DNA tests just for the fun of it because it has become easier and useful in determining not just ethnicity, but also health risks and in finding long-lost family members. Testing your genealogy allows people to take tests to determine if a person really is biologically related – a feat that has helped so many legal cases in the past.

DNA test have also allowed people to find their biological parents, and for coroners and police to find the family members of unidentified bodies. Recently, the police managed to catch the serial killer, rapist, and burglar only known as the “Golden State Killer” because his relatives’ DNA were in an open-source genealogy site. GEDmatch was a place where people volunteered to donate their DNA, and since then, it’s become a genealogy database for law enforcement looking for similar DNA matches.

The Disadvantages

However, the more people voluntarily send their DNA just for the fun of knowing how Asian they are, there’s the disadvantage of the fact that a company now has your DNA in their database. While that may not seem like a big deal for some, others would argue that it poses a lot of threats to your privacy and safety. Hackers would be able to steal your DNA and sell it on the black market, while the company that has your sample can use your DNA for other purposes without your consent.

While there’s a high chance of accuracy for up to your 2nd cousin, there are also several factors that affect how accurate results will be. If you are on the receiving end of stem cell or bone marrow transplants, that part of your body will match DNA with the donor. Identical twins also share DNA, so keeping them in a database may be difficult to execute.

If you want to try out a DNA test to find out your ancestors’ ethnicities, you can find multiple reputable companies offering to help at low costs. However, before you do so, it’s important to understand what the process is, what happens to your DNA, and if you think its advantages are worth the possible drawbacks.